Hard Starts / Long cranks with Low ICP at Cold

2006 F250 Lariat 6.0 PS 4x4

I just had to deal with hard starts, long cranks at cold with low ICP. Got it running late on Tuesday, 6/9/2026. Rather annoying since in March 2022, I updated the STC fitting in the HPOP, Standpipes and Dummy plugs amongst many other things. All Ford Genuine parts. Turned out to be the upper piece with check valve of the passenger side standpipe. Specifically, the bottom O-ring, or do we call that a D-ring, where it inserts into the lower long tube?

To diagnose, I first checked the anti-drain valve in the Oil Filter Housing and verified it would hold for 2-1/2 hours.
Then I purchased test port plug adapters for the ICP and IPR port. Decided to go with the IPR port to check both sides without having to power the IPR valve. Loud hissing out of the oil fill tube was the result.

Off came the passenger valve cover. Pressured it again and air came from the backside near the standpipe and injector there. Could not verify specifically the culprit from air testing alone. The high pressure oil rail (HPOR) obscured it, but certainly knew the vicinity of the leak at that point. When I pulled the standpipe, the upper piece came out by itself and the culprit was revealed.



Upper passenger standpipe piece.

I pulled the HPOR while I was at it, because I wanted to gauge the health of my ball tube / nipple cup O-rings and Injector D-rings. The nipples were all snug, just as they were last time. They wouldn't budge under considerable pressure, although I didn't overdo it. They're perfectly aligned to the injectors. Years back, I did purchase the HHC diesel replacement O-rings and a Dorman Ball Tube socket if such was needed. I took the opportunity to test the Dorman socket fit to the nut as well as the tube alignment port. Fit was good on all of them for that rail.



High Pressure Oil Rail with Dorman Ball Tube Socket

After reinstalling the high pressure oil rail and standpipe replacement, air tested again, pressure held. Put everything back together and took three cranks with some time for the starter to rest in between cranks to build pressure. Started almost immediately on the third crank. Test drove and all is good.


DashDAQ XL

More details and pics below.

Autoenginuity prior to going under hood:

ICP voltage = 0.24 V KOEO, 0.6 V cranking
FICM voltage = 48.5 V KOEO, 48 V cranking
FICM Sync = 0 KOEO, 1 cranking
IPR Duty Cycle = 14.84% KOEO, 84.77% cranking
ICP = 346.14 psi cranking

To test my oil filter anti-drain valve, I used a 1/2" CPVC pipe cut to about 7-1/2" long, capped on the bottom end to press the valve closed. Cap pressed on tightly, so did not glue. Drilled holes every inch from the bottom with the last two holes 1/2" apart at top near the fill level for a crude ruler to track oil level and allow fill-in to minimize buoyancy.

Prior to using, I cleaned off cutting debris and burrs inside and out, and used a finger clamp to hold it in place. Then cranked the truck by jumping the starter cable to the passenger battery's positive stud. Filter housing filled to the bottom threads in about 8 seconds (me counting, not using a watch). Watched it hold for two minutes, snapped a pic, covered it with a plastic shopping bag, and left it for 2-1/2 hours. It held to the same level -- about 1/16” shy of the reference hole.



After acquiring the final pieces I needed for air testing the high pressure oil system, I opted to air test through the IPR port. I do have an OTC test adapter for the ICP port, but wanted to test both sides and avoid the limited time constraint powering the IPR closed, which I could do with Autoenginuity.

Before opening anything sensitive, I blew the engine off with compressed air. Especially around the valve covers, FICM, IPR, turbo, etc.

Prior to using the DEWHEL IPR test plug, I compared it dimensionally side by side with my IPR valve, then used an OD caliper to compare all OD’s including the threads, shaft and both O-rings. All checked good and equivalent.

A 1-3/16” socket (a little over 30 mm) fits the DEWHEL IPR plug. Not every ½” socket set will include that large a size. My SK set goes up to 1-1/8”. My Craftsman set goes to 1-1/4”. I applied Sil-Glyde to the O-rings and threads. It threaded smoothly.

I used the Lisle 68210 IPR socket. It fit and worked well, but it’s 3/8" drive. When I first set up with a 3/8 ratchet, extension and u-joint to break the IPR loose, the ⅜ u-joint and extension flexed more than I liked. Since I had a ½ to ⅜ drive adapter, I switched to a 1/2" ratchet, extension and u-joint, and broke the IPR valve loose with ease.







Prior to reinstalling the valve cover, I added ½ qt of oil to the HPOR via the ICP port to account for some spillage when it was removed. I don’t know how much difference that makes in the amount of cranking to build pressure, but figure it helped some. Dip stick was at middle of operating range prior to starting this diagnosis and repair.

For removal and installation of the passenger valve cover, a 12 mm ratcheting box wrench is useful for the back bottom two bolts where the Evap box makes for tight working space. Likewise, a stubby/compact T30 bit socket in the same area for the HPOR bolts. Remove any oil in the T30 bolt holes prior to reinstalling.

Incidentally, after removing the FICM, I found chafing damage to the coolant hose as shown. I tie-wrapped it to prevent further contact for the time being.





Air test setup:

DEWHEL IPR test plug adapter, 1-3/16” socket (or equivalent metric) needed - Amazon
Goodyear 3' x 3/8" hybrid hose (1/4 MNPT threads) - Amazon
Milton S-655 Tee fitting (1/4 FNPT) - Amazon
Winters 2" Dial, 0-160 psi Air Gauge, 1/4 MNPT bottom mount - Amazon
Husky ball valve, 1/4 NPT - Home Depot
1/4 npt air fittings and quick connects - Home Depot and Northern Tool

Useful tools and items:

Headlamp
Telescoping magnet
Mechanics mirror or bore scope
Length of hose or mechanics stethoscope for leak detection
Lisle 68210 IPR socket or similar
Lisle 26610 T30 Torx socket (¼ drive), or similar low profile/stubby T30 socket for HP oil rail
12 mm hex / allen bit socket for standpipes and dummy plugs
12 mm, 8 mm or 5/16” ratchet wrenches for valve cover near evap box and ficm rear bolts
15/16” deep socket for ICP sensor
1-3/16” socket for IPR test plug adapter (size may vary with the brand?)
OD caliper for verifying IPR test plug adapter
½” Cpvc pipe with cap and a finger clamp for checking oil anti-drain valve
Ball tube / nipple cup socket

Torque Specs (from 2006 Super Duty Workshop Manual):

Valve cover bolts: 80 lb-in, (12 mm socket, ratcheting wrench near Evap box)
ICP sensor: 9 lb-ft / 108 lb-in, (15/16” deep socket)
IPR valve: 37 lb-ft, (special cut-out socket)
HPOR bolts: 10 lb-ft / 120 lb-in, (T30 torx bit socket, low profile/stubby near Evap box)
Standpipe and dummy plug: 60 lb-ft, (12 mm hex bit socket for updated, 10 mm for originals)

Relevant part numbers:

Standpipe (single): 6E7Z-9A332-A
Standpipes & Dummy plugs: 6E7Z-9A332-B
Dummy plugs (pack of 2): W302908
O-rings & screen for IPR: 3C3Z-9H529-A
HPOP one-piece STC kit: 4C3Z-9B246-F

 

Some creative troubleshooting thanks for sharing your oil filter drainback test

good find on that oring on standpipe

should be good to go